The effect of temperature and PH on enzyme activity

Question 1

What is the effect of temperature on enzyme activity in mammals?

Answer 1

• Peaks at 35 degrees Celsius
• Above the body temperature the enzyme activity starts to decrease
• The heat of the molecules in the system will increase. As the temperatue of the system is increased, the internal energy of the molecules in the system will increase- causing the enzyme activity to decrease

Question 2

Why is the optimum temperature range for enzymes in mammals is different to reptiles?

Answer 2

• Mammals are endothermic- bodies evolved by 37 degrees

- Reptiles are ectothermic- their enzymes must be able to function at a wider range of temperatures

Question 3

Why is the pH in the small intestine different to the stomach?

Answer 3

• pH in the intestine is around 7

- Stomach pH is around 4 due to the hydrochloric acid secreted in the stomach

Question 4

What is rennin?

Answer 4

• Coagulates / curdles milk in the stomach

- Most active at 37 degrees

Question 5

Would the digestive enzymes in reptiles to be active at 37 degrees?

Answer 5

• Probably be active at a wider range of temperatures that enzymes in mammals because reptiles body temperature fluctuates because they are ectothermic